My first finished attempt at Homestar Runner fanfiction was Reality is a Harsh Mistress, which is hosted on both
fanfiction.net and
deviantART. It was written in December 2006/January 2007, and, being something I wrote more than two years ago, I don't think it's that great. But it's still the only multichapter Homestar Runner fic I've done where the plot doesn't require them to be out of character for practically the whole story. I really should do another someday. It's about Strong Bad waking up in a world where everyone's human and have sensible names. I kind of made it up as I went along. I don't do that anymore.
That was awesome. It's got to be my favorite fanfic ever.